From a58e2c5c4928ae8031ee60a97f2ab4f863aff8cb Mon Sep 17 00:00:00 2001
From: Victor Stinner <victor.stinner@gmail.com>
Date: Fri, 20 May 2016 12:08:12 +0200
Subject: [PATCH] Issue #26741: POSIX implementation of
 subprocess.Popen._execute_child() now sets the returncode attribute using the
 child process exit status when exec failed.

---
 Lib/subprocess.py | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/Lib/subprocess.py b/Lib/subprocess.py
index 642c7f21822..41a9de10f5e 100644
--- a/Lib/subprocess.py
+++ b/Lib/subprocess.py
@@ -1524,9 +1524,14 @@ class Popen(object):
 
             if errpipe_data:
                 try:
-                    os.waitpid(self.pid, 0)
+                    pid, sts = os.waitpid(self.pid, 0)
+                    if pid == self.pid:
+                        self._handle_exitstatus(sts)
+                    else:
+                        self.returncode = sys.maxsize
                 except ChildProcessError:
                     pass
+
                 try:
                     exception_name, hex_errno, err_msg = (
                             errpipe_data.split(b':', 2))